1. Field of the Invention
The present invention relates to an improved teeth prosthesis for an upper maxilla and to a method for mounting or removing a suprastructure of said prosthesis on or from a fixed infrastructure.
2. Brief Description of the Prior Art
It is known in the art to embody teeth prosthesis for a lower maxilla, said teeth prosthesis being of the type comprising an infrastructure, a suprastructure and means for a removable attachment of the suprastructure with the infrastructure.
The infrastructure comprises:
at least two implants, advantageously at least 3 and preferably four to six, each implant having opposite ends, one end of each implant being anchored in the bone of the lower maxilla while the opposite end is sticking out of the gingiva and defines a head to said implant, PA1 one connection bar having a fore part and two opposite rear ends, said connection bar being shaped and sized to be substantially facing the gingiva of the lower maxilla, and PA1 means for removably fastening the connection bar with and against each head of said implants. PA1 a member made of cast metal or alloy, said member having a fore part and two rear ends, said member having an intrados provided with an opening giving access to a housing provided in the member, said housing being of such size and depth to allow the connection bar to be housed therein, PA1 a saddle immovably attached with the member, and PA1 a set of teeth immovably attached with the member and the saddle. PA1 a device comprising a sleeve, especially a cylindrical sleeve, immovably attached with a corresponding end of the member, said cylindrical sleeve being provided with a lateral opening, and a pin slidably mounted inside the sleeve and movable between two distinct positions, a first distinct position being defined when the pin is not facing the lateral opening and a second distinct position being defined when the pin is facing the lateral opening, PA1 a bore provided in a protouberance, especially a small protuberance, near a corresponding end of the connection bar, said protuberance being shaped and sized to be housed in a corresponding cylindrical sleeve through the lateral opening of said cylindrical sleeve, to be co-axial with a longitudinal axis of the cylindrical sleeve and to be removably engaged by the pin. PA1 said infrastructure comprising: PA1 said suprastructure comprising: PA1 said means for a removable attachment of the suprastructure with the infrastructure comprising: PA1 for mounting the suprastructure on the infrastructure, one only have to house both sliding surface one against the other and to fasten the rear ends of the first member with the corresponding rear ends of the connection bar; PA1 for removing the suprastructure from the infrastructure, one only have to unfasten the rear ends of the first member from the corresponding rear ends of the connection bar and to move the sliding faces away from each other.
The suprastructure comprises:
The means for a removable attachment of the suprastructure with the infrastructure comprises fastening means that are respectively immovably attached with a corresponding rear end of the member, for removably attaching them with corresponding ends of the connection bar. Preferably such fastening means comprises:
Advantageously, each of aforesaid fastening means are of the type of those sold under the trade mark MK1 (Polydental Laboratory, BELGIUM).
However, even though aforesaid prior art teeth prothesis can work correctly when installed on the lower maxilla, it become unusable for the upper maxilla because it was not possible to prevent the fore part (i.e. the anterior part) of the suprastructure to separate from the infrastructure without having to negatively affect the esthetic appearance of the fore part of said prosthesis. In fact there is generally not enough space to provide a conventional lock at the anterior part.
Therefore, there was a very strong need for a way allowing to efficiently fasten the fore part of a suprastructure of a teeth prosthesis for an upper maxilla, comprising a fixed infrastructure and a removable suprastructure, without affecting the esthetic characteristic of the fore part of said suprastructure.
Also, there was a strong need to obtain a simple and easy method for mounting and removing a superstructure of a teeth prosthesis for an upper maxilla. Indeed, methods actually known for mounting and removing a suprastructure on or from an fixed infrastructure are laborious.